I'm 33, and I've had a carry permit since I was 22. In 11 years, I've drawn my weapon twice. Has it changed my attitude, no. It has however, changed my awareness. I find myself constantly scanning for oddities these day, given all the public shootings. I read and followed (and still follow) Colonel Cooper's 4 golden rules of gun safety on recommendation of a friend of mine who served in Vietnam (yes, he is much older than I but we share common hobbies in shooting and collecting firearms) suggested. For those of you who don't know them, I've taken the liberty of copying and pasting them here along with Colonel Cooper's "weapons state of readiness" and state of mind. (I didn't wanna type all this so I just copied it and pasted from Wikipedia)

1) All guns are always loaded. Even if they are not, treat them as if they are.
2) Never let the muzzle cover anything you are not willing to destroy. (For those who insist that this particular gun is unloaded, see Rule 1.)
3) Keep your finger off the trigger till your sights are on the target. This is the Golden Rule. Its violation is directly responsible for about 60 percent of inadvertent discharges.
4) Identify your target, and what is behind it

If you can master those 4 things, you can safely conceal carry without worry. Cooper went on to label the states of a gun, as follows: (Obviously this is also dependent on the type of handgun, originally designed for a 1911)

-White: Unaware and unprepared. If attacked in Condition White, the only thing that may save you is the inadequacy or ineptitude of your attacker. When confronted by something nasty, your reaction will probably be "Oh my God! This can't be happening to me."
-Yellow: Relaxed alert. No specific threat situation. Your mindset is that "today could be the day I may have to defend myself". You are simply aware that the world is a potentially unfriendly place and that you are prepared to defend yourself, if necessary. You use your eyes and ears, and realize that "I may have to shoot today". You don't have to be armed in this state, but if you are armed you should be in Condition Yellow. You should always be in Yellow whenever you are in unfamiliar surroundings or among people you don't know. You can remain in Yellow for long periods, as long as you are able to "Watch your six." (In aviation 12 o'clock refers to the direction in front of the aircraft's nose. Six o'clock is the blind spot behind the pilot.) In Yellow, you are "taking in" surrounding information in a relaxed but alert manner, like a continuous 360 degree radar sweep. As Cooper put it, "I might have to shoot."
-Orange: Specific alert. Something is not quite right and has your attention. Your radar has picked up a specific alert. You shift your primary focus to determine if there is a threat (but you do not drop your six). Your mindset shifts to "I may have to shoot that person today", focusing on the specific target which has caused the escalation in alert status. In Condition Orange, you set a mental trigger: "If that person does "X", I will need to stop them". Your pistol usually remains holstered in this state. Staying in Orange can be a bit of a mental strain, but you can stay in it for as long as you need to. If the threat proves to be nothing, you shift back to Condition Yellow.
-Red: Condition Red is fight. Your mental trigger (established back in Condition Orange) has been tripped. "If 'X' happens I will shoot that person".

(This paragraph I do not know the truth of, as I have never been in the USMC........The USMC uses condition Black, although it was not originally part of Cooper's Color Code. Condition Black: Catastrophic breakdown of mental and physical performance. Usually over 175 heartbeats per minute, increased heart rate becomes counter productive. May have stopped thinking correctly. This can happen when going from Condition White or Yellow immediately to Condition Red.)

It looks like a lot, but after reading it a couple times it's common sense. If you know it, it constantly runs through your head while carrying, and kind of reinforces good habits and controlled states of mind. Honestly, I think every person who applies for an FFL should be required to at least read those before being issued a permit. As much as I am in favor of having a more armed society, and urge people to get their CWL, here is GA the process is so simple anyone can go do it in an hour. Just fill out a form that's very similar to the ATF 4473 (New gun purchase form all non-private sales fill out) pay $68 and go get fingerprinted. Assuming you pass the background check, your CWL shows up in 4-6 weeks. A few years back, it was only $17. It's some of the people I have seen getting the license that concerns me. They type that fire a shot and the range and swing around with a loaded gun in hand and say ooh ooh look I hit the middle.